Fluctuation of Blood Chemical Components in Dairy Cows before and after Feeding

Abstract

Cows were given the control diet (Group A, 7 cows) high protein, and diet (Group CP, 5 cows) or high starch diet (Group ST, 6 cows), and blood was sampled and examined by chemical components before, 2 hr after, and 4 hr after the morning feeding. In Group A blood sampled 2 hr after feeding showed lower contents of total cholesterol (TCHO), beta lipoprotein (β-LIPO), and ammonium (NH₃) as compared with samples before feeding. In Group CP samples at 2 hr postfeeding were higher in blood urea nitrogen (BUN) and lower in glucose (GL), while higher contents of triglyseride (TG) and BUN were seen in Group ST. In Group contents of CP, TG, β-LIPO and NH₃ were higher than those in Group A at 2 hr postfeeding. At 4 hr after feeding such temporary fluctuations were much smallerin range, indicating that blood should be sampled for metabolic profile test (MPT) at 4 hror later after the morning feeding but before the next feeding.